On the Role of Delay Tolerant Networks and Contact Graph Routing in Direct-to-Satellite IoT
Résumé
This paper explores the integration of Delay-Tolerant Networking (DTN) and Contact Graph Routing (CGR) within Direct-to-Satellite Internet of Things (DtS-IoT) networks, utilizing the FLoRaSat discrete-event simulator based on Omnet++, By incorporating a DTN model and the CGR algorithm, the study evaluates the efficacy of these technologies in optimizing data routing and handling across emerging Low-Earth Orbit (LEO) satellite networks. The research delves into various satellite fleet configurations, including Star and Delta constellations, across different numbers of orbital planes and with the integration of opportunistic Inter-Satellite Links (ISLs). Results using the FLoRaSat simulator demonstrate that the DTN store-carry-and-forward approach over ISLs, enhanced by CGR, significantly reduces end-to-end delivery delays. Specifically, the implementation achieves an average end-to-end delivery delay as low as 10 minutes in 4-plane Star constellations with 24 satellites and immediate forwarding in 8-plane Delta constellations of equivalent size, underscoring the potential of DTN and CGR to improve the efficiency and reliability of emerging DtS-IoT.